Project 2b8 CRC sugar Industry Innovation through Biotechnology Research Project Final Report Alternative sugars: new options for the sugar industry.

View/Open

Date

Author

Metadata

Abstract

Sugarcane has a highly effective carbohydrate biosynthetic and storage metabolism that has facilitated its use for the production of sucrose. Sugars are increasingly seen as low-cost, renewable organic resources which can be modified to produce food ingredients and industrial raw materials. For the sugar industry, alternative sugars offer a means of diversification in an area close to the existing core business. However a major restriction to development of alternative products has been ownership of enabling intellectual property by third parties. This project aimed to identify alternative sugars with desirable commercial properties and capture the IP to enable their production. The initial phase of the project was a scoping study to identify novel, naturally occurring sugars and enzyme systems that may be involved in their manufacture by collating information from the literature and patent databases. Sugars that occur naturally in sugarcane and closely related species were also examined for potential as higher value products. Preferred candidates were simple modifications of sucrose where the gene sequences encoding the enzymes were available and no prior IP existed. Four sugars with potential applications as alternative sweeteners or chemical feedstocks were identified. Two of the candidate sugars could be either purchased directly or made by chemical synthesis from a purchased precursor. The remaining two candidate sugars were not available commercially and could not be synthesised easily. We proposed to make these sugars by cloning and expressing the genes that encode the enzymes from their native sources and then using the enzymes to synthesise the novel sugars in vitro. Two enzymes were expressed and characterised. Although neither of these enzymes carried out the predicted reactions, both enzymes were new; one is a dehydrogenase and the other is a glucosidase acting on gluco-oligosaccharides. The potential value of any novel sugar depends on its physical and sensory properties. For application as an alternative sweetener, a novel sugar ideally needs to be as sweet as sucrose but offer health benefits, particularly low cariogenicity (tooth decay) and low calorie-yield. We developed methods that can be used in the laboratory to test industry-relevant properties of sugars, specifically sweetness, cariogenicity and digestibility. A set of commercially available sugars, including several alternative sweeteners, was used to test the assays and provide a comparison with the novel sugars. Sweetness relative to sucrose and glucose was determined by a two-way preference ingestion assay with Drosophila melanogaster (fruit flies). Production of acid by the oral bacterium Streptococcus mutans was used as an assay to detect potentially cariogenic sugars. Calorie yield of sugars was measured by assays for digestibility by yeast invertase and rat α-glucosidase/sucrase. We also tested whether the sugars were able to inhibit the digestion of sucrose, and whether the sugars could promote the growth of ‘healthy’ bacteria in the gut. The results showed that two alternative sugars derived from sucrose have the properties required for an alternative sweetener. We also identified a disaccharide which is sweet-tasting and able to inhibit the digestion of sucrose. Further research will be required to develop an economic production system for these candidate sugars. The tests developed in this project also identified some interesting relationships between sugar structure and sensory or nutritive properties. Further analysis of these relationships may allow design of new sweeteners with optimal properties. CRC Sugar Industry Innovation through Biotechnology The outcome of this work is an improved ability to develop new sugar derivatives as alternative sweeteners. The information and tools developed by the project will assist future efforts to exploit new options for diversification in the sugar industry.

Please use this identifier to cite or link to this item

Collections

Copyright in this document is owned by Sugar Research Australia Limited (SRA) or by one or more other parties which have provided it to SRA, as indicated in the document. With the exception of any material protected by a trade mark, this document is licensed under a Creative Commons Attribution-NonCommercial 4.0 International licence (as described through this link). Any use of this publication, other than as authorised under this licence or copyright law, is prohibited.

In referencing this document, please use the citation identified in the document.

Disclaimer:

In this disclaimer a reference to "SRA" means Sugar Research Australia Ltd and its directors, officers, employees, contractors and agents.

This document has been prepared in good faith by the organisation or individual named in the document on the basis of information available to them at the date of publication without any independent verification. Although SRA does its best to present information that is correct and accurate, to the full extent permitted by law SRA makes no warranties, guarantees or representations about the suitability, reliability, currency or accuracy of the information in this document, for any purposes.

The information contained in this document (including tests, inspections and recommendations) is produced for general information only. It is not intended as professional advice on any particular matter. No person should act or fail to act on the basis of any information contained in this document without first conducting independent inquiries and obtaining specific and independent professional advice as appropriate.

To the full extent permitted by law, SRA expressly disclaims all and any liability to any persons in respect of anything done by any such person in reliance (whether in whole or in part) on any information contained in this document, including any loss, damage, cost or expense incurred by any such persons as a result of the use of, or reliance on, any information in this document.

The views expressed in this publication are not necessarily those of SRA.

Any copies made of this document or any part of it must incorporate this disclaimer.

My Account

Copyright in this document is owned by Sugar Research Australia Limited (SRA) or by one or more other parties which have provided it to SRA, as indicated in the document. With the exception of any material protected by a trade mark, this document is licensed under a Creative Commons Attribution-NonCommercial 4.0 International licence (as described through this link). Any use of this publication, other than as authorised under this licence or copyright law, is prohibited.

In referencing this document, please use the citation identified in the document.

Disclaimer:

In this disclaimer a reference to "SRA" means Sugar Research Australia Ltd and its directors, officers, employees, contractors and agents.

This document has been prepared in good faith by the organisation or individual named in the document on the basis of information available to them at the date of publication without any independent verification. Although SRA does its best to present information that is correct and accurate, to the full extent permitted by law SRA makes no warranties, guarantees or representations about the suitability, reliability, currency or accuracy of the information in this document, for any purposes.

The information contained in this document (including tests, inspections and recommendations) is produced for general information only. It is not intended as professional advice on any particular matter. No person should act or fail to act on the basis of any information contained in this document without first conducting independent inquiries and obtaining specific and independent professional advice as appropriate.

To the full extent permitted by law, SRA expressly disclaims all and any liability to any persons in respect of anything done by any such person in reliance (whether in whole or in part) on any information contained in this document, including any loss, damage, cost or expense incurred by any such persons as a result of the use of, or reliance on, any information in this document.

The views expressed in this publication are not necessarily those of SRA.

Any copies made of this document or any part of it must incorporate this disclaimer.